Imaging biomarkers in the idiopathic inflammatory myopathies

Abstract

Idiopathic inflammatory myopathies (IIMs) are a group of acquired muscle diseases with muscle inflammation, weakness, and other extra-muscular manifestations. IIMs can significantly impact the quality of life, and management of IIMs often requires a multi-disciplinary approach. Imaging biomarkers have become an integral part of the management of IIMs. Magnetic resonance imaging (MRI), muscle ultrasound, electrical impedance myography (EIM), and positron emission tomography (PET) are the most widely used imaging technologies in IIMs. They can help make the diagnosis and assess the burden of muscle damage and treatment response. MRI is the most widely used imaging biomarker of IIMs and can assess a large volume of muscle tissue but is limited by availability and cost. Muscle ultrasound and EIM are easy to administer and can even be performed in the clinical setting, but they need further validation. These technologies may complement muscle strength testing and laboratory studies and provide an objective assessment of muscle health in IIMs. Furthermore, this is a rapidly progressing field, and new advances are going to equip care providers with a better objective assessment of IIMS and eventually improve patient management. This review discusses the current state and future direction of imaging biomarkers in IIMs.

Diagnostic value of apparent diffusion coefficient of psoas muscles for evaluating complications in patients with Crohn’s disease

“…Previous studies have confirmed DWI and ADC efficacy as useful clinical tools to identify the pattern of intramuscular disorders based on changes of free water motion and increasing cellularity [ 14 , 16 , 26 – 32 ]. Meyer et al .…”

Sporadic Inclusion Body Myositis at the Crossroads between Muscle Degeneration, Inflammation, and Aging

“…In recent years, muscle MRI has emerged as an important tool in the diagnosis of muscle disorders due to its ability to highlight affected muscle by revealing atrophy, fat infiltration and signs of inflammation [ 32 ]. In sIBM, MRI changes have been reported in both upper and lower limbs, are more severe in distal segments, and usually have an asymmetric pattern [ 32 , 33 , 34 , 35 ]. Fat infiltration is commonly seen in MRI scans [ 33 , 35 , 36 , 37 ].…”

Mitochondrial defects in sporadic inclusion body myositis—causes and consequences

“…sIBM is a male-predominant disease that has a prevalence of 5–71 per million in the whole population ( Tsamis et al, 2022 ). Typically occurring after the age of 50 ( Snedden et al, 2022 ), sIBM is characterized by progressive and asymmetric weakness in the quadriceps and long finger flexors rather than an acute or subacute symmetrical proximal muscle weakness seen in other subtypes of IIM ( Zubair et al, 2023 ). Individuals with sIBM experience a loss of muscle strength at a rate of 3.5%–28% per year ( Zubair et al, 2023 ) and can become wheelchair-bound at a median time of 10.5 years after the disease onset ( Skolka and Naddaf, 2023 ).…”

“…Typically occurring after the age of 50 ( Snedden et al, 2022 ), sIBM is characterized by progressive and asymmetric weakness in the quadriceps and long finger flexors rather than an acute or subacute symmetrical proximal muscle weakness seen in other subtypes of IIM ( Zubair et al, 2023 ). Individuals with sIBM experience a loss of muscle strength at a rate of 3.5%–28% per year ( Zubair et al, 2023 ) and can become wheelchair-bound at a median time of 10.5 years after the disease onset ( Skolka and Naddaf, 2023 ). Respiratory compromise and dysphagia are common risk factors for premature death in sIBM patients, which may account for their slight but significantly shortened lifespan when compared to healthy subjects ( Shelly et al, 2021 ).…”